The hearing to scheduled for Tuesday to discuss whether Tsarnaev should have more access to things like television and radio, prayer services and visitors while he awaits trial, the Boston Herald reported.
U.S. District Judge George A. O'Toole Jr. ruled the ACLU would not be permitted to speak on Tsarnaev's behalf, and that a memorandum the ACLU Foundation of Massachusetts submitted in support of its position be stricken from the public record.
"While there may be no positive rule forbidding it, in my judgment a trial court presiding over a criminal prosecution should not receive or consider volunteered submissions by non-parties except as may be specifically authorized by statute ... or other authority," O'Toole wrote in his ruling.
Last week, the ACLU filed the memorandum that stated it planned to fight for Tsarnaev's right to have access to his attorneys.
The ACLU had not commented on O'Toole's ruling.